To understand the relationship between computer and musician, you have to first understand the relationship between computer and human. For many years, that interaction has primarily involved some gesture – the click of a mouse, the swipe of a finger – and an accompanying interface abstraction. But now, from phones to desktops, computers are not only data acquisition gadgets for photos and text and various hand gestures. They’re increasingly looking inward at their human masters, connecting to the biological feedback systems our bodies themselves use. And music is a perfect window into that world.

It’s a big moment for bio-interfacing and music. Performer and media artist Marco Donnarumma, having earned acclaim for his Xth Sense bio-interface, is now unleashing the tools he has used to the world, in the form of documentation, open source hardware, and free software. The Canadian Electroacoustic Community (CEC) is turning over an issue to the topic of “Biotechnological Performance Practice,” with Mr. Donnarumma at the helm as guest editor. And in Berlin, workshops, installations, and live performances around the topic culminate this week with a show opening as part of the BodyControlled series at LEAP Gallery (co-presented with CDM). That event will allow the artistic and scientific communities to come together to examine the issue.

But what does it mean to make something a “bio interface,” anyway?

The LEAP opening offers a variety of answers. From the scientific world, Portugese-born researcher Pedro Lopes of Potsdam, Germany’s Hasso-Plattner-Institute will present “Human-Computer Interaction: Artistic and Scientific perspectives on augmenting our bodies.” The three artists provide three different angles. Donnarumma looks to the muscular system, literally listening in on the sounds produced by muscle movements. Claudia Robles Angel (Colombia, by way of Germany) uses a brain interface in her piece INsideOUT. I’ll present a brief audiovisual performance using a more common biofeedback method, galvanic skin response.

These methods all go beyond interface in the sense of a mouse, keyboard, or touchscreen. “The central principle underpinning the Xth Sense (XS),” writes Donnarumma, “is not to ‘interface’ the human body to an interactive system, but rather to approach the former as an actual and complete musical instrument.”

All three of the sensors are external. They each “listen in” on the body’s internal functions from the skin. The EEG interface senses electrical activity on the scalp produced by the brain working away inside. (Think about those cartoon characters when steam starts to rise from their head as they think hard – in the electrical sense, that’s exactly what happens.) I chose the galvanic skin response measurement simply because it’s dead-simple and easy to replicate (I’ll share some commentary on that soon). These sensors measure electrical conductance, which changes as you control sweat glands. It doesn’t sound like it’ll work, but it does, and everything from biofeedback systems to those “psychic” cellophane fish that are supposed to curl up if you’re in love operate on the principle.

The EEG and biofeedback systems are useful in that they can help people to learn to control their bodies – for instance, to relax. But Donnarumma’s system is the most novel as a musical instrument, integrating the body and computer in a kind of singular feedback system for performance. The results are expressive, and fascinatingly, get more directly at what happens when you move a muscle.

The system listens in on these sounds – your body’s very own LFO – and thus even tiny muscle movements can be mapped to intricate control of musical performance.

But don’t take my word for it. Thanks to an open approach to the project, Marco is sharing the results with everyone – and you can give it a try yourself. He writes CDM:

I’m quite happy to announce the first public release of the Xth Sense. After over one year of work, the dedicated website is finally on-line.
It includes tutorials, schematic, info, codes, and screenshots, all one needs to know to build her own XS biophysical instrument. There is also the chance to order a DIY Kit (although they are already sold out, there are few waiting lists).

The website is going to be constantly updated, with more tutorials, and some videos too. So keep an eye on it.
Next, I will create a mailing list, in which all XS users can share questions and ideas.

It’s great to match the XS release with this series of event at LEAP in Berlin. This will be one of the few nights completely dedicated to biologically informed music… pretty much looking forward to play with you guys, so I would warmly recommend to come along and spend a night of visceral music with us. In between, I’ve prepared a special piece for the gig, it’s something unreleased and never heard before, hope it will be an intriguing surprise.
I love Berlin, and actually the first XS workshop took place there, at the NK. It’s always thrilling to come back.
Hope to see some of you soon!”

eContact! volume 14, number 2 is out in late July. The theme will be “Biotechnological Performance Practice / Pratiques de performance biotechnologique.” Publisher CEC is Canada’s national electroacoustics association, defining electroacoustics as ranging “from ‘pure’ acousmatic and computer music to soundscape and sonic art to hardware hacking and beyond.”

2. The Performance/Exhibition (Berlin):

Friday night in Berlin, we turn all of this into live performance. (Then and over the weekend, the exhibition will also let visitors try out some of the bio-sensing methods themselves in a project the venue calls “Open Stage.” We’ll be hearing about the results of workshops, too.)

I don’t like the word “first,” but the LEAP event is certainly rare – and perhaps a sign of things to come. It’s an event solely dedicated to bio-interfacing as performance technique.

I guess I’d better not prepare too much and hope I’m rather nervous, as that’ll make my performance – and, subsequently, working to relax – go better.

3. Try Xth Sense Yourself

DIY Xth Sense. Kits are sold out, but finding the parts won’t be difficult…

The XS is a free and open project. You can build your own Xth Sense biophysical sensors from scratch.
Building the wearable sensor is very easy (you need to solder literally 4 components) so it requires only a basic knowledge of soldering.
The schematic, the parts list, and a tutorial are available below. Building an XS sensor by hand takes between 1 or 4 hours, depending on your skill and your tools